Technologies for 3-D CT of gas temperature and flow distributions based on the MAP estimation with local iterations which is referring acoustic time-of-flight through non-linear observation process is proposed. The technologies are featured signal processor with pre-whitener and complex absolute detection for received signal to cope with unknown and non-linear phase shift. The proposed technologies has provided the standard deviation of the identified time-of flight was one tenth as that of the previous technique. The technologies has been shown to effectively estimate the distributions in large scale chambers and outdoor environments.